The present invention relates to a clamping device, and more particularly to a clamp for securing a pump jack pole to a wall or roof brace or the like.
Upright poles are utilized in conventional scaffolding arrangements on which ride pump jacks supporting horizontal scaffolding platforms. Typically, such upright poles are made of aluminum and have a rubberized surface on one side. When assembling the scaffolding unit the upright poles must be secured to the wall or roof of the building on which the scaffolding is placed. One or two V or X-shaped braces are typically used for this purpose. The braces usually have a pair of legs coupled to the building. The head end of the brace is terminated with a U-shaped bracket which is pivotally connected to a U-shaped yoke which surrounds the pole to hold the pole in place. The yoke includes two side plates and a transverse plate member through which a bolt extends which is tightened by an outer wing nut to tighten the clamp onto the pole.
Clamping devices of the foregoing type are disclosed, for example, in applicant's U.S. Pat. Nos. 4,432,435 and 4,446,945.
The clamping device shown in applicant's U.S. Pat. No. 4,432,435 has a transverse plate member provided with a hook insertable into a slot of one of the side plates of the U-shaped yoke and a tooth insertable into a slot of another parallel side plate of the yoke. This caused some operational and installation difficulties in trying to manipulate the clamp into a closed position while simultaneously tightening the wing nut onto the pole.